Automatic generation of alloreactivity-reduced donor lymphocytes and hematopoietic stem cells from the same mobilized apheresis product.

INTRODUCTION: In vitro or in vivo depletion of alloreactive T cells can facilitate haplo-identical hematopoietic stem cell transplantation (HSCT). Very satisfactory transplant outcomes were thus reported for TCRαß/CD19-depleted hematopoietic stem/progenitor cell (HSPC) grafts. The current semi-automatic manufacturing process on the CliniMACS Plus, although robust, still requires a significant amount of manual labor to be completed. Towards advancing and further facilitating large scale cell processing, a new TCRαß/CD19 depletion module combined with the previously described CD45RA depletion module (to serve as allo-reactivity attenuated donor lymphocyte infusion) was established on the CliniMACS Prodigy. METHODS: We evaluated six apheresis products from G-CSF-mobilized volunteer donors which were split automatically by the Prodigy, one portion each depleted of CD45RA+ or of TCRαß+ and CD19+ cells. We investigated critical quality attributes for both products. Products were assessed for recovery of HSPCs and mature subsets, as well as depletion efficiency of targeted cells using flow cytometry. Effects of apheresis and product age post 48 h storage at 2-6 °C as well as freeze-thawing on product viability and recovery of WBC and HPSCs were assessed by flow cytometry. RESULTS: Ten sequential automatic processes were completed with minimal hands-on time beyond tubing set installation. Depletion efficiency of CD45RA+ resp. TCRαß+ and CD19+ cells was equivalent to previous reports, achieving mean depletions of 4 log of targeted cells for both products. HSPC products retained TCRγδ+ and NK cells. 48 h storage of apheresis product was associated with the expected modest loss of HSPCs, but depletions remained efficient. Depleted products were stable until at least 72 h after apheresis with stem cell viabilities > 90%. Freeze-thawing resulted in loss of NK cells; post-thaw recovery of viable CD45+ and HSPCs was > 70% and in line with expectation. CONCLUSION: The closed, GMP-compatible process generates two separate medicinal products from the same mobilized apheresis product. The CD45RA-depleted products contained functional memory T cells, whereas the TCRαß/CD19-depleted products included HSPCs, TCRγδ+ and NK cells. Both products are predicted to be effectively depleted of GVH-reactivity while providing immunological surveillance, in support of haplo-identical HSCT.

Personality traits in chronic pain patients are associated with low acceptance and catastrophizing about pain.

OBJECTIVE: Pain acceptance is considered important for mental well-being with better functional outcomes for chronic pain patients. The present study explored whether pain-related variables (pain severity, pain interference, pain duration, and pain catastrophizing) and non-pain-related variables (personality traits) influence acceptance and additionally examined the interrelationship between the influencing variables and acceptance. METHODS: One hundred patients with chronic pain from a multidisciplinary pain centre completed self-report questionnaires on acceptance, pain severity, interference of life, pain duration, pain catastrophizing, and personality. RESULTS: Pain severity, pain interference, and pain duration had no significant correlations with acceptance. Pain catastrophizing and most personality traits were significantly and negatively related to acceptance. Regression analyses revealed that of all personality traits, the avoidant personality trait explains most variance of acceptance. Subsequent mediation analysis indicated that catastrophizing about pain mediated the relationship between the avoidant personality trait and acceptance. CONCLUSION: The findings indicate that acceptance is influenced by catastrophizing and avoidant personality traits. The clinical implication might be that acceptance-oriented treatments may prove less successful in chronic pain patients with more pronounced avoidant personality traits. Extra focus on a reduction of the frequency of pain catastrophizing might be helpful.

Evaluation of the risk factors for shedding Salmonella with or without antimicrobial resistance in swine using multinomial regression method.

A multinomial logistic regression method was used to investigate the risk factors for antimicrobial resistance (AMR) in Salmonella isolated from faecal samples collected on 80 Ontario swine farms in Canada. The samples were classified into three groups including Salmonella-negative samples (S-), Salmonella-positive samples without AMR (S+AMR-) and Salmonella-positive samples with AMR (S+AMR+). The samples collected directly from pigs had a greater chance to be positive for Salmonella with AMR compared to those samples collected from the pen floor. The odds of culturing Salmonella with or without AMR was higher if pelleted feed was used compared with mash or liquid feed (P < 0.001). The faecal samples collected on farrow-to-finish farms had a significant lower chance of testing positive for Salmonella with multidrug resistance than the samples from grow-finisher farms (P = 0.004). The chance of culturing Salmonella without AMR on farms with a continuous system was higher than on farms with an all-in/all-out system (P = 0.009). However, there was no significant association between the flow system and recovery of Salmonella with AMR. The larger farms were more likely to be in S+AMR+ group than in S- group (P < 0.001) whereas herd size did not appear as a risk factor for being in S+AMR- group compared with S- group. These findings indicate that although on-farm antimicrobial use is one component of resistance, there might be other farm management factors that also affect the development of emerging resistant bacterial foodborne pathogens on swine farms. Finding different risk factors for shedding Salmonella with or without antimicrobial resistance would help to take the appropriate approach to each group if a control programme were to be implemented or an intervention applied.

The characterization of Salmonella serovars isolated from apparently healthy slaughtered pigs at Addis Ababa abattoir, Ethiopia.

We looked for Salmonella in all 278 apparently healthy pigs slaughtered between September 2004 and May 2005 at the only pig-slaughtering slaughterhouse in Addis Ababa, Ethiopia. We used standard methods and tested caecal contents, mesenteric lymph nodes, and carcass swabs from each pig (missing only one carcass swab). Of the 278 pigs, 120 (43%) were positive; of the 833 samples 173 (21%) were positive. Thirty-three percent of the isolates were multi-resistant (including 46/48 isolates of S. Hadar, but none of the 39 isolates of S. Eastbourne or of the 37 of S. Saintpaul). Resistance to streptomycin (32.4%), tetracycline (31.8%) and nitrofurantoin (27.2%) was relatively high. The most common pattern of MDR observed was to nitrofurantoin, streptomycin and tetracycline (Resistance type NitStrTet). Our results indicate that salmonellae are prevalent in pigs slaughtered at Addis Ababa abattoir and a large proportion of the isolates were multi-drug resistant.

Risk factors for antimicrobial resistance among fecal Escherichia coli from residents on forty-three swine farms.

Fecal Escherichia coli (n = 555) were isolated from 115 residents on 43 farrow-to-finish swine farms to determine the prevalence of antimicrobial resistance and associated risk factors. Susceptibility to 21 antimicrobials was determined and the overall prevalence of antimicrobial resistance was 25.8%. Pair-wise difference in prevalences of resistance to individual antimicrobials was significant between isolates from residents on farms that fed medicated swine rations compared to those that did not (p = 0.013). Cross-resistance among antimicrobials of same class and multidrug-resistance were observed. Logistic regression models revealed the following risk factors positively associated with antimicrobial resistance: use of antimicrobials in pigs on farms; number of hours per week that farmers spent in their pig barns; handling of sick pigs; and intake of antimicrobials by farm residents. This study indicates that occupational exposure of farmers to resistant bacteria and use of antimicrobials in pig farming may constitute a source of resistance in humans, although the human health impacts of such resistance is unknown. The consumption of antimicrobials by farmers appeared to constitute a significant risk for resistance development. Fecal E. coli from farm residents may act as a reservoir of resistance genes for animal and/or human pathogens.

Antimicrobial activity of essential oils and structurally related synthetic food additives towards selected pathogenic and beneficial gut bacteria.

AIMS: To assess the potential of essential oils and structurally related synthetic food additives in reducing bacterial pathogens in swine intestinal tract. METHODS AND RESULTS: The antimicrobial activity of essential oils/compounds was measured by determining the inhibition of bacterial growth. Among 66 essential oils/compounds that exhibited > or =80% inhibition towards Salmonellatyphimurium DT104 and Escherichia coli O157:H7, nine were further studied. Most of the oils/compounds demonstrated high efficacy against S. typhimurium DT104, E. coli O157:H7, and E. coli with K88 pili with little inhibition towards lactobacilli and bifidobacteria. They were also tolerant to the low pH. When mixed with pig cecal digesta, these oils/compounds retained their efficacy against E. coli O157:H7. In addition, they significantly inhibited E. coli and coliform bacteria in the digesta, but had little effect on the total number of lactobacilli and anaerobic bacteria. CONCLUSIONS: Some essential oils/compounds demonstrated good potential, including efficacy, tolerance to low pH, and selectivity towards bacterial pathogens, in reducing human and animal bacterial pathogens in swine intestinal tract. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has identified candidates of essential oils/compounds for in vivo studies to develop antibiotic substitutes for the reduction of human and animal bacterial pathogens in swine intestinal tract.

Acquisition of resistance to extended-spectrum cephalosporins by Salmonella enterica subsp. enterica serovar Newport and Escherichia coli in the turkey poult intestinal tract.

Salmonella enterica subsp. enterica serovar Newport resistant to the extended-spectrum cephalosporins (ESCs) and other antimicrobials causes septicemic salmonellosis in humans and animals and is increasingly isolated from humans, animals, foods, and environmental sources. Mechanisms whereby serovar Newport bacteria become resistant to ESCs and other classes of antimicrobials while inhabiting the intestinal tract are not well understood. The present study shows that 25.3% of serovar Newport strains isolated from the turkey poult intestinal tract after the animals were dosed with Escherichia coli harboring a large conjugative plasmid encoding the CMY-2 beta-lactamase and other drug resistance determinants acquired the plasmid and its associated drug resistance genes. The conjugative plasmid containing the cmy-2 gene was transferred not only from the donor E. coli to Salmonella serovar Newport but also to another E. coli serotype present in the intestinal tract. Laboratory studies showed that the plasmid could be readily transferred between serovar Newport and E. coli intestinal isolates. Administration of a single dose of ceftiofur, used to prevent septicemic colibacillosis, to 1-day-old turkeys did not result in the isolation of ceftiofur-resistant E. coli or Salmonella serovar Newport. There was a remarkable association between serotype, drug resistance, and plasmid profile among the E. coli strains isolated from the poults. This study shows that Salmonella serovar Newport can become resistant to ESCs and other antibiotics by acquiring a conjugative drug resistance plasmid from E. coli in the intestines.

Antibiotic resistance of Salmonella isolated from hog, beef, and chicken carcass samples from provincially inspected abattoirs in Ontario.

The emergence of antimicrobial-resistant Salmonella organisms, especially Salmonella Typhimurium DT104, has been reported in many countries, including the United States and Canada. The purposes of this study were to determine the antimicrobial resistance patterns of Salmonella isolated from hog, beef, and chicken carcasses from provincially inspected abattoirs in Ontario and to determine the agreement between the agar dilution method and the microbroth dilution method for measurement of antimicrobial resistance of the isolates. Antimicrobial resistance of Salmonella isolates from hogs (n = 71), beef (n = 24), and chicken (n = 295) to amikacin, ampicillin, cephalothin, chloramphenicol, ciprofloxacin, gentamicin, streptomycin, sulfamethoxazole, and tetracycline was determined using the two methods. None of the 390 isolates were resistant to ciprofloxacin at levels of 0.125 microg/ml. All chicken and hog isolates were sensitive to amikacin, whereas all beef isolates were sensitive to both amikacin and gentamicin. Multiple antimicrobial resistance (resistance to more than one antimicrobial) was found in 29% of bovine isolates and 42% of porcine isolates using both methods for testing and in 42% by the agar dilution and 33% by the microbroth dilution methods in the chicken isolates. Overall, there was good agreement between the two test methods for resistance to most of the antimicrobials, with disagreement found in the results in 1.3% of the isolates for ampicillin and sulfamethoxazole, 8.2% for streptomycin, 5.6% for cephalothin, and 1.0% of the isolates for tetracycline. The lack of agreement between the two test methods was found mostly among the chicken isolates.

Verotoxins in commensal Escherichia coli in cattle: the effect of injectable subcutaneous oxytetracycline in addition to in-feed chlortetracycline on prevalence.

Using a self-paired observational study, the association between therapeutic oxytetracycline use and the prevalence of virulence genes in commensal Escherichia coli (E. coli) from cattle was examined. Faeces were collected from 39 yearling bulls prior to and after treatment with oxytetracycline and from 44 untreated animals. Between samplings all animals received in-feed chlortetracycline for 16 days. Five E. coli were isolated from each sample and tested by a polymerase chain reaction (PCR) capable of detecting all verotoxin (vt) genes. Positive isolates were further tested with a multiplex PCR to detect vt1, vt2, eaeA and hlyA. For vt, 23 animals were positive at both samplings, 26 negative at both samplings, 22 negative animals became positive and 12 positive animals became negative. Sixty-eight per cent of the discordant pairs changed from vt-negative to vt-positive (95% CI 48-80) suggesting pressure toward becoming vt-positive perhaps due to the transfer of genes due to mixing of cattle in the months between samplings or an effect of chlortetracycline.

Chronic pain therapy: an evolution from solo-interventions to a holistic interdisciplinary patient approach.

The treatment of chronic pain patients has changed over years. Anaesthesiologists treat pain patients, their skills in locoregional anaesthesia techniques and their pharmacological knowledge being a unique resource to reduce pain. However, the International Association for the Study of Pain provides more and more scientific evidence that chronic pain is a biopsychosocial event and that its diagnosis and treatment should be considered in a multidisciplinary frame. Nevertheless, in practice we can't deny the fact that there are several steps in the process in which the patient himself decides if he wants such an approach or not. The 'motivating' phase is a very important pretherapy and basic condition to start up a holistic pain treatment. Therefore, at the Ghent University Hospital Pain Clinic, we focused in a first step how to motivate our pain patients to take part in a multidisciplinary diagnostic examination, the second step is motivate them for an interdisciplinary treatment when it is indicated. We diagnose the four most important pain components: the sensory, myofacial, autonomic and psychosocial problems. The patient who is initially examined by the anaesthesiologist, will also be evaluated by the psychologist and the physician in rehabilitation medicine. By this way each component is mapped and a final (holistic) diagnosis can be made. In a weekly half-a-day meeting, the different specialists discuss the patients and put forward an interdisciplinary treatment plan. On several moments, the patients' treatment progress will be discussed and redirected if necessary. So, we hope to obtain an optimal result and avoid overtreatment and too invasive pain treatment.

[Standing behavior in horses after inhalation anesthesia with isoflurane (Isoflo) and postanesthetic sedation with romifidine (Sedivet) or xylazine (Rompun)]. / Aufstehverhalten bei Pferden nach Inhalationsnarkose mit Isofluran (Isoflo) und postanästhetischer Sedierung mit Romifidin (Sedivet) bzw. Xylazin (Rompun).

Isofluorane is a modern, only slightly depressive inhalation anaesthetic with excellent pharmacologic characteristics in use in equine medicine. In contrast to halothane, isofluorane is hardly broken down in the liver, but is eliminated by the lung. It low solubility in blood permits excellent control of anaesthesia. However, due to its swift elimination from the organism there is heightened risk of premature recovery from isofluorane anaesthesia. In this study the recovery phases of 96 horses were monitored for its duration and the animals' physical coordination. The horses were divided into four groups. Two groups were sedated with xylazine, one of which received postanaesthetic sedation with xylazine, the other saline solution only. The other two groups were sedated with romifidine, either with or without postanaesthetic sedation after general anaesthesia. In this study the horses of Group 4, sedated with 0.02 mg/kg BW romifidine at the moment of extubation, showed the best recovery phase. The number of attempts to arise was reduced and coordination was better. Similar results were obtained by postanaesthetic sedation with 0.2 mg/kg BW xylazine (Group 2). Premedication with 0.08 mg/kg BW romifidine without postanaesthetic sedation (Group 3) could be carried out at mean duration of anaesthesia of 85 minutes with no negative effects observed during the recovery period. Premedication with xylazine without postanaesthetic sedation (Group 1) is not to be recommended, as the number of attemps to stand up was significantly higher and coordination was either weak or significantly poorer than in the other three groups. The results of this study show that post-anaesthetic sedation of horses with an alpha 2-adrenoceptor agonist can improve the recovery phase after inhalant anaesthesia with isofluorane in regard to the number of attempts to arise and the animals' physical coordination.

Prognostic value of non-sustained ventricular tachycardias after acute myocardial infarction in the thrombolytic era: importance of combination with frequent ventricular premature beats.

PURPOSE: of this study was to re-evaluate the association between ventricular arrhythmias and long-term mortality after acute myocardial infarction (AMI) in the thrombolytic era. METHODS: MITRA (maximal individual therapy in patients with AMI) is a multicenter registry of 54 hospitals in Germany investigating patients with AMI. RESULTS: 2420 patients received Holter ECG. Positive Holter ECG was defined: > or =10 ventricular premature beats (VPB)/h, or > or =4 couplets/d, or > or =1 non-sustained ventricular tachycardia (nsusVT)/d, or their combination. Mortality rates (median 17 months) were 6.5% without ventricular arrhythmias, with > or =10 VPB/h 15.2% and with the combination of > or =10 VPB/h plus either > or =4 couplets/d or > or =1 nsusVT/d 23.4%. In multivariate analysis, none of the ventricular arrhythmias alone correlated with mortality. There was a significant association between mortality and the combination of > or =10 VPB/h plus > or =4 couplets/d (OR 2.3) or > or =10 VPB/h plus > or =1 nsusVT/d (OR 2.8). CONCLUSION: Non-sustained VTs are only associated with poor prognosis if combined with frequent VPBs.

Diversity in antimicrobial resistance and other characteristics among Salmonella typhimurium DT104 isolates.

Multiresistant Salmonella enterica subspecies enterica serovar Typhimurium definitive type 104 (S. Typhimurium DT104 or DT104) bacteria are important pathogens in animals and humans. DT104 isolates are often called pentaresistant strains that spread clonally. The purpose of this study was to determine phenotypic, genotypic, and epidemiologic characteristics of 175 S. Typhimurium DT104 strains isolated from food-producing animals in Canada. More than 90% of the isolates were resistant to ampicillin (Amp), chloramphenicol (Chl), florfenicol (Flo), sulfisoxazole (Sul), and tetracycline (Tet), 53% of the isolates were additionally resistant to spectinomycin (Spc) and streptomycin (Str), and 28% to kanamycin (Kan) and neomycin (Neo). Sixty-one percent of the strains harbored a single 60-MDa plasmid, 21% contained 60- and 2.0-MDa plasmids, and 4% had 60, 4.6- and 2.0-MDa plasmids. Resistance to Kan and Neo was encoded by the aminoglycoside aphA-1 gene on 2.0-MDa plasmids, whereas resistance to trimethoprim (Tmp) and Sul was encoded by the dhfrIb gene on 4.6-MDa plasmids. Polymerase chain reactions (PCR) showed the presence of integrons with the ant (3")-Ia aminoglycoside adenyltransferase and the bla(PSE-1) beta-lactamase gene cassettes, and the presence of the flost gene in all but one strain resistant to Spc and Str, Amp, and Chl and Flo, respectively. DT104 isolates from cattle at six feedlots represented a separate clone; they were sensitive to Str and Spc and lacked the ant (3")-Ia gene. Pulsed-field gel electrophoresis (PFGE) using Bln I, Spe I, and Xba I resulted in 15, 12, and 8 PFGE patterns, respectively. In summary, we observed considerable diversity in phenotypic, genotypic, and epidemiological characteristics among the DT104 isolates.

Changes in the prevalence of resistant Escherichia coil in cattle receiving subcutaneously injectable oxytetracycline in addition to in-feed chlortetracycline compared with cattle receiving only in-feed chlortetracycline.

Information about the prevalence of antibiotic resistance in commensal enteric bacteria is of interest because these bacteria are potential indicators of selection pressure on enteric bacteria and represent a reservoir of resistance genes in potentially pathogenic bacteria. This study reports changes in the prevalence of resistance to antibiotics in commensal Escherichia coli from cattle receiving either subcutaneously injectable oxytetracycline in addition to in-feed chlortetracycline or only in-feed chlortetracycline. Resistance to 19 antibiotics was examined. The use of injectable oxytetracycline in addition to in-feed chlortetracycline was significantly associated (P < 0.05) with an increase in the prevalence of resistance only to chloramphenicol and sulfisoxazole.

[Giant cavernous hemangioma of the scalp]. / Kavernöses Riesenhämangiom der Kopfhaut.

Cavernous hemangiomas of the scalp associated with vascular tumors of the skull occur rarely in older patients. Giant hemangiomas can cause complications secondary to extensive bleeding. Here we report on a 78-year-old female presenting with a giant ulcerated cavernous hemangioma of the scalp. Before admission to the hospital, she had suffered from severe bleeding of the vascular tumor, with resulting anemia. Because of her cardiovascular disease, the tumor mass, and possible vascular connections to osseous hemangiomas, complete surgical removal of the hemangioma was not indicated. Therefore the superficial ulceration was covered with a split skin transplant. After complete wound healing, no further bleeding occurred.

Chronic fatigue syndrome in the psychiatric practice.

BACKGROUND: Chronic fatigue syndrome (CFS) is a complex syndrome with a psychiatric comorbidity of 70-80%. A psychiatric interview is necessary in order to exclude psychiatric illness and to identify psychiatric comorbidity. Studies have demonstrated that in general medical practice and in the non-psychiatric specialist practice, physicians tend to underdiagnose psychopathology in patients with CFS. There are many questions unanswered about the treatment of CFS Aim: Typical issues for the psychiatric practice are reviewed: psychiatric comorbidity, dysregulation of the PHA-axis and the treatment of CFS. CONCLUSIONS: Depression, somatization, sleeping disorders and anxiety disorders are the most important psychopathological symptoms found in CFS patients. CFS should not be regarded as a masked (somatoform) depression. Although the results from neuroendocrinological studies assessing the hypothalamic-pituitary-adrenal axis (HPA-axis) are inconsistent, they suggest that there is a subgroup of CFS patients suffering from a discrete dysregulation of the HPA-axis resulting in basal hypocortisolaemia. These findings, however, do not reveal a causal relationship. Antidepressants do not seem to have a positive influence on the symptom of fatigue, but appear to be beneficial in alleviating the symptoms of depression and social functioning. Cognitive behaviour therapy and graded exercise show a significant improvement on fatigue and other symptoms and are the only treatments available for CFS patients.

Emergence of Salmonella typhimurium definitive type 104 (DT104) as an important cause of salmonellosis in horses in Ontario.

Salmonella Typhimurium definitive type 104 (DT104) has emerged as a common cause of salmonellosis in humans and cattle, yet previous reports involving horses are sparse. This study reports the emergence of DT104 as an important pathogen in horses in Ontario. The first clinical case of DT104 infection at the Ontario Veterinary College was identified in 1997. Seventeen cases of DT104-associated salmonellosis were identified between 1997 and 2000. In 2000, 12 of 13 cases of salmonellosis were due to DT104. Salmonellosis in horses due to DT104 is of concern, since the organism is multiresistant to antibiotics and poses increased zoonotic risk. Phage type distribution of Salmonella isolates should be monitored to determine whether DT104 will remain a prevalent equine pathogen.

Trends in antimicrobial resistance of Salmonella isolated from animals, foods of animal origin, and the environment of animal production in Canada, 1994-1997.

The purpose of our study was to determine the occurrence, magnitude, trends, and relationships regarding antibiotic resistance of Salmonella isolated from animals, animal food products, and the environment of animals. We examined 621 strains of 67 different serovars isolated in 1994, 721 strains of 75 different serovars isolated in 1995, 1,219 strains of 83 different serovars isolated in 1996, and 1,336 Salmonella strains of 92 different serovars isolated in 1997, for resistance to 17 antibiotics at one to three different concentrations with the agar dilution method. The overall resistance magnitude regressed from 9.2% in 1994 to 8.1% in 1997. Resistance to streptomycin (30.4% of 3,897 isolates), tetracycline (27.3%), and sulfisoxazole (23.7%) was highest. Resistance to streptomycin, tetracycline, kanamycin, and gentamicin declined during the 4-year period. Notable increases in resistance to ampicillin, chloramphenicol, and neomycin occurred during the 1994-1997 years. None of the isolates was resistant to amikacin. None of the isolates was resistant to ciprofloxacin at 1, 2, and 4 microg/ml. Salmonella bredeney isolates from turkeys showed a decreased sensitivity to ciprofloxacin and were resistant at the low level of 0.125 microg/ml, but none of these isolates was resistant at 1 microg/ml. Resistance to nalidixic acid correlated significantly with decreased sensitivity to ciprofloxacin; 122 of 127 (96%) isolates resistant to nalidixic acid at 32 microg/ml were resistant to ciprofloxacin at 0.125 microg/ml but sensitive at 1 microg/ml. Resistance to S. typhimurium to each of the seven antibiotics ampicillin, chloramphenicol, kanamycin, neomycin, streptomycin, sulfisoxazole, and tetracycline increased persistently during each of the years 1994-1997, but none of the S. typhimurium isolates showed decreased sensitivity to ciprofloxacin. Clinical isolates of Salmonella were twice as frequently resistant to the antimicrobials in the test panel than isolates obtained during surveys. Salmonella isolates from turkeys were more frequently resistant than isolates from pigs, cattle, and chickens.

Negative interference of endogenous phytochrome B with phytochrome A function in Arabidopsis.

To study negative interactions between phytochromes, phytochrome B (phyB) overexpressor lines, the mutants phyA-201, phyB-4, phyB-5, phyD-1, phyA-201 phyB-5, phyA-201 phyD-1, and phyB-5 phyD-1 of Arabidopsis were used. Endogenous phyB, but not phytochrome D (phyD), partly suppressed phytochrome A (phyA)-dependent inhibition of hypocotyl elongation in far-red light (FR). Dichromatic irradiation demonstrated that the negative effect of phyB was largely independent of the photoequilibrium, i.e. far-red light absorbing form of phytochrome formation. Moreover, phyB-4, a mutant impaired in signal transduction, did not show a loss of inhibition of phyA by phyB. Overexpression of phyB, conversely, resulted in an enhanced inhibition of phyA function, even in the absence of supplementary carbohydrates. However, overexpression of a mutated phyB, which cannot incorporate the chromophore, had no detectable effect on phyA action. In addition to seedling growth, accumulation of anthocyanins in FR, another manifestation of the high irradiance response, was strongly influenced by phyB holoprotein. Induction of seed germination by FR, a very low fluence response, was suppressed by both endogenous phyB and phyD. In conclusion, we show that both classical response modes of phyA, high irradiance response, and very low fluence response are subject to an inhibitory action of phyB-like phytochromes. Possible mechanisms of the negative interference are discussed.